Witch Wars - S6-E21
Visible crew/equipment: While the demons are watching Witch Wars at the bar, when the show's host, Corr, is holding an athame he tells viewers the winner will be awarded a serious power boost, then just as Corr says, "Since the shapeshifter..," in the shot of the demon bar patrons, we see the T-mark (it is not part of the Witch Wars show) taped to the floor under the table. That T-mark is visible again in at least three following shots. (00:23:35)
Answer: That was a mistake in the series.
Also, the episode is called 'Babies First Demon' and this alone tells us that it's Wyatt's first time in the field (so to speak) and as the sisters say, they've done a good job of clearing up their own magical messes so far. Nobody really knows how advanced Wyatt's powers are, or will become. That's why the cleaners appear, to nip things in the bud. The Cleaners didn't want to chance that the sisters could clean Wyatt's magic up, just incase they couldn't. Therefore intervening themselves, just in case.